Protective cover for the blades of spatulas, &amp;c.



c. WQBENSON.

PROTECTIVE COVER FOR THE BLADES 0F S'PATULAS, &c.

APPLICATION FILED NOV. 21,. 1915.

1,242, 11 5. v Patented Oct. 9,1917

= nome n 6. ZMBenSon I onnnnns wrianivson, or DULUTH MINNESOT I""PROTECTIVE oovnn ron THE BnAnEs or sPATULAs, 8w.

To all whom it may concern; I

Be it known that I, CHARLns BENSON, a citizen oflth'e United States,residing at Duluth, in the, county of St. Louis and State of Minnesota,have invented certain new and useful Improvements in Protective Coversfor the Blades of Spatulas,"&c., of which the following is va,specification.

This invention relates to an improvement; ininstruments, such?v assp'atulas used by dentists, vdruggists, and; others employ ng similarinstruments. The use'of the ord'i nary: spatula with a .steel bladepresents numerous -disadvantages particularly where the instrument isemployed by a dentistin the mixing of cement. lThei-liquid constitu entof dental cements ordinarily contains a certain percentage ofphosphoricacid and when such .cements are im-iXed with a steel spatula blade theblade is liable to become tarnishedand frequently the cement is dis--colored. Furthermore, dental cements dry quickly and it is frequentlyfound difficult to remove cement which has dried and caked, upon thebladens thecement '1 S lnsoluble in,

water and diiiicult to remove by scraping,

The present invention, therefore, aims to' provide'a spatula the-bladeof which is,pro-s tected by a cover or ,sheath which does not.

in any way interfere with the use of the spatula nor detract fromtheresiliency orv flexibility of the blade and which-cover or sheathwill be of such material as not to be in any way affected by acids andmay. be soine'xpensive :as to permit of a new sheath being applied tothe blade each time the spatula is used, 'thereby avoiding "thenecessity" of cleaning the spatula blade after use and avoidinglikelihood ofdiscoloring olf Specification of Letters Patent.

App lication filed ifIoveinber 27,1915. Serial N o. I 4

In 7 the accompanying drawings} 1 Figure 1 1s a perspective vlewofia'dental spatula equipped with the improvement em b'odying thepresent invention;

2 vis aFdetail longitudinal sectional v1ew through the blade and sheathillustrate ing in full lines the normal condition of the' sheathand in.dotted linesthe man er in' which the walls of :the sheath are to," be

Patented 7 movedapart so as to release the sheath for] removal;

Fig. 8'i's a verticalftr'ansverse sectional view on the line 3 3 of F 2illustrating tion in full-lines;

F'g. 4 i a perspective View ofthe 'sheath removed;

portion of the spatula'blade r the walls .of thesheath' in normalcondition in dotted lines, and in spread apart condi i a 7 J 1Fig.5 isa, detail perspective viewsof a' .In the accompanying drawings, thenumeral 1 indicates ingeneral the handle of the spatulaand Q'thebladethereof, the blade except. asjhereinafter stated being vof the vordinary form and resilient and flexibleto the desired degree. The shankwhicheon nectsthe' blade ,2 with the handle 1 is indicated; by thenumeral 3 and by reference to the drawings it will/be observed that thelateral edges 4 of the =bladeare parallel'for substantially tho entirelength of the blade;

butthatadjacent the point of juncture of the blade with the shank 3these edges converge ,in, the direction ofthe shank, as iin dicated thenumeral At a suitable point. and preferably immediately forwardly of the.pointof juncture of the inner end of the blade2 with the shank 3, eachside or face of the :blade is formed with iapro; -.:tuberance 6 havingan abrupt rearwardly presented face 7 constituting a locking shoulder,the purpose of which will be presently explained. The surface of theprotuberance 6 aside from the abrupt face 7 thereof is convex and mergesinto the face of the blade upon which it is formed.

The blade sheath indicated in general by the numeral 8 is formed fromany suitable material, such-for example as celluloid and the saidsheath'is flat sided and of a mar- ,ginal contour to conform to themarginal contour ofthe blade, the" sheath being arranged to snugly fitthe blade when the blade is inserted therein. In its initial form thewalls of the sheath lie in contact or substantially in contact so thatwhen the sheath is appliedto the blade the said walls will lie snuglyagainst the opposite faces of the blade. It is stated above that thesheath has a marginal contour corresponding to the marginal contour ofthe blade but this isnot strictlytrue for the reason that the side edgesof the sheath are parallel throughout the length of the sheath so thatadjacent the open end or throat of the sheath, indicated at 9, thesheath is'interiorly slightly wider than the blade between its edgeportions 5." The object in view in thus proportioning the blade andsheath will be presently stated. At the throat 9 of the sheath the walls8 are thickened or otherwise suitably reinforced, as indicated at 10,and immediately forwardly of the thickened portion each wall is formedwith an opening 11. In preparing the spatula for use, the blade thereofis inserted in one of the sheaths and as the side walls of the sheath atthe mouth 9 thereof reach the protuberances G and ride upwardly upon theconvex faces of the protuberances the said walls will be spread apartuntil their reinforced portions 10 have passed over the protuberanceswhereupon the side walls of the sheath by their inherent resiliency willspring toward each other and the protuberanccs 6 will be received withinthe openings 11, the walls of the said openings neXt adj acent thereinforcements 1O resting against the abrupt shoulders 7 and therebyserving to securely hold the sheath in place upon the blade.

Inasmuch as the side edges of the sheath Copies of this patent may beobtained for the locking shoulders 7 of the protuberanees 6 as the bladeis withdrawn or the sheath is removed.

Having thus described the invention,

'what is claimed as new is:

l. The combination with the blade of a spatula or the like, the saidblade being provided with a shoulder, of a sheath for the said bladereinovably fitted thereto and flexible with the blade, and provided withmeans vfor cooperation with the shoulder for holding the sheath in placeupon the blade.

2. The combination'with the blade of a spatula or the like, the saidblade being provided with a protuberance and the edges of the bladeadjacent the protuberance being inwardly offset, of a sheath for theblade removably fitted thereto and flexible there-.

reinforcement with openings to receive the said protuberances upon theblade.

l. In a device of the class described, a spatula or the like having ablade provided upon its opposite faces with protuberances each having anabrupt shoulder, and a sheath removably fitted to the blade and providedat its open end with a reinforcement and provided in its walls adjacentthe reinforcement with openings to receive the said protuberances uponthe blade, the edges of the said blade being inwardly offset adjacentthe said protuberances and the said sheath adjacent its said open endbesaid blade. 7

In testimony whereof, I afliX my signature CHARLES WV. BENSON. [Lisa]five cents each, by addressing the Commissioner of Patents,

Washington, D. C.

mg of greater width interiorly than the

